Mkv Demuxer

mkv-demuxer is a javascript library for demuxing matroska, webm files in the browser. It can be used to:

• Get media information of a video
• Get all frames of a video
• Get a certain frame at a given timestamp of a video

Installation

npm install mkv-demuxer -S

Usage

Constructor

import MkvDemuxer from 'mkv-demuxer'
const demuxer = new MkvDemuxer()

API

initFile(file, filePieceSize)

Params: file, filePieceSize

• file File - The file to be parsed
• filePieceSize Number - The file piece size parsed each time

const filePieceSize = 1 * 1024 * 1024
await demuxer.initFile(file, filePieceSize)

getMeta()

Returns: Promise<meta>

• meta - The meta infomation of the file
  • info
    • duration Number
    • title String
    • ...
  • video
    • codecID String
    • codecPrivate ArrayBuffer
    • width Number
    • Height Number
    • displayWidth Number
    • displayHeight Number
    • language String
    • ...
  • Audio
    • codecID String
    • codecPrivate ArrayBuffer
    • bitDepth Number
    • channels Number
    • rate Number
    • ...

const meta = await demuxer.getMeta()

getData()

To get all frames of a video.

Returns: Promise<data>

• data - The video data of the file
  • cues Array - The keyframes of the file
    • cueTime Number
    • cueTrackPositions
      • cueClusterPosition Number
      • cueRelativePosition Number
      • cueTrack Number
      • ...
    • ...
  • videoPackets Array
    • start Number
    • end Number
    • size Number
    • timestamp Number
    • isKeyframe Boolean
    • keyframeTimestamp Number
  • audioPackets Array
    • start Number
    • end Number
    • size Number
    • timestamp Number

const data = await demuxer.getData()

seekFrame(timestamp)

Params: timestamp

• timestamp number

Returns: Promise<frame>

• frame
  • start Number
  • end Number
  • size Number
  • timestamp Number
  • isKeyframe Boolean
  • keyframeTimestamp Number

const frame = await demuxer.seekFrame(10)

reset()

To reset the demuxer.

Example

import MkvDemuxer from 'mkv-demuxer'
const demuxer = new MkvDemuxer()
const filePieceSize = 1 * 1024 * 1024
await demuxer.initFile(file, filePieceSize)
const meta = await demuxer.getMeta()
const data = await demuxer.getData()
const frame = await demuxer.seekFrame(10)

Additional notes

This library is based on jswebm and has made a series of optimizations. It solves the memory problem, optimizes exception handling, and provides several useful APIs.